Recently, the number of people who breed aquarium fishes and water plants in large and small aquariums at home and shops is growing.
Because aquarium fishes in aquariums move dynamically and have beautiful colors and shapes, if such aquariums are installed in houses or shops, it provides an interior decoration effect. Therefore, the number of people who install aquariums is increasing.
In order to raise aquarium fishes in aquariums in which water plants are put, an adequate amount of carbon dioxide must be put in the aquarium so as to grow the water plants normally.
For instance, Korean Patent No. 1,188,232 discloses a “carbon dioxide supply device for aquarium” which can supply an adequate amount of carbon dioxide into an aquarium.
The conventional carbon dioxide supply device has the structure that a valve capable of being adjusted by a user is mounted at an outlet of a gas barrel, in which carbon dioxide is compressed and stored, so that carbon dioxide is supplied into the aquarium through a supply hose according to opening and closing of the valve.
However, all prior arts as well as the above-mentioned conventional carbon dioxide supply device have a huge problem in operation because they have no means for showing a supply state in real time when carbon dioxide is supplied.
In other words, although the supply amount of carbon dioxide is changed suddenly by internal situations or external factors of the aquarium, such prior arts cannot allow users to realize immediately. Additionally, because the prior arts do not have any means for properly controlling the supply amount according to all situations, people demand more effective systems for solving the above problems.